Glossary “head land ring” Definition:
Top compression ring with an L-shaped cross section.
h
head on view
Glossary “head on view” Definition:
Compares the test panel to the vehicle straight on , or perpendicular. Also refers to a reference point to determine front end alignment angles.
head pressure
Glossary “head pressure” Definition:
Pressure of the refrigerant from the discharge valve through the lines and condenser to the metering-device inlet.
head bolts
Glossary “head bolts” Definition:
Bolts that fasten the cylinder heads to the engine block.
HDV
Glossary “HDV” Definition:
Heavy Duty Vehicle
H/E
Glossary “H/E” Definition:
Hall – Effect
head
Glossary “head” Definition:
1). Part of an engine that covers the top of the cylinders and pistons and usually contains the combustion chambers and valve train. 2). That part of a compressor that covers the valve plates and separates the high side from the low side of an A/C system.
hdr
Glossary “hdr” Definition:
Acronym form of Header
HDR-CKP
Glossary “HDR-CKP” Definition:
High Data Rate-Crankshaft Position Sensor
HDT
Glossary “HDT” Definition:
Heavy Duty Thermoplastic
HD
Glossary “HD” Definition:
Heavy Duty, or Hard Drive
H/D
Glossary “H/D” Definition:
Heavy Duty
HDB
Glossary “HDB” Definition:
Heavy Duty Braided
HDC
Glossary “HDC” Definition:
Heavy Duty Cooling
HDC-CTO
Glossary “HDC-CTO” Definition:
Heavy Duty Cooling – Coolant Temperature Override
HCDSS
Glossary “HCDSS” Definition:
High Clutch Drum Speed Sensor (4R44E & 4R55E)
HCV
Glossary “HCV” Definition:
Heat Control Valve
HC-CO meter
Glossary “HC-CO meter” Definition:
Device using an infrared sensor to measure the amount of HC, in parts per million and CO, in percent, in the vehicle exhaust.
HCB
Glossary “HCB” Definition:
Heated Crankcase Breather
H'back
Glossary “H’back” Definition:
Hatchback